CMake parallel build: fixes #8

 - Used the CMake 'target property' `Fortran_MODULE_DIRECTORY` to ensure that the static
   and shared libraries may be build at once without stepping on eachothers toes
 - The module file generated during each of the builds (static vs shared) will be identical,
   so it doesn't matter that one is not installed, etc.

Author: zbeekman

CMakeLists.txt

@@ -103,7 +103,8 @@ set_target_properties ( ${LIB_NAME}
   PREFIX lib
   SOVERSION ${VERSION_MAJOR}.${VERSION_MINOR}
   VERSION ${VERSION}
-  LIBRARY_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/lib )
+  LIBRARY_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/lib
+  Fortran_MODULE_DIRECTORY ${CMAKE_BINARY_DIR} )
 
 #--------------------------
 # Build the test executable